BACKGROUND: The relapses of colorectal cancer (CRC) frequently occur in 2 years period after the time of diagnosis. However, a considerable proportion of patients relapse in the late period. AIM: The aim of the present study is to define the factors predicting the early and late relapses of patients with early stage CRC. MATERIALS AND METHODS: A total of 250 patients with CRC, who relapsed after completion of primary therapy between 2005 and 2014, were enrolled in the study. According to the time of relapse, patients were divided into two groups as follows: Early relapse (Group 1: Within first 24 months) and late relapse (Group 2: Later than 24 months). Clinicopathological features and survival rates of the two groups were compared. RESULTS: Of 250 patients, 151 (60.4%) (Group 1) were relapsed within the first 24 months after completion of the primary therapy and 105 (39.6%) were relapsed later than 24 months. The patients with T1-T2 and Grade I tumors were relapsed in late period (P < 0.05). The rates of administered systemic chemotherapy and targeted therapies after relapse were similar in both groups. The median overall survival rates in patients relapsed within the first 24 months and after 24 months were 18 months and 21 months, respectively (P = 0.05). CONCLUSIONS: In patients with CRC, the time duration of relapse after completion of the operation and adjuvant chemotherapy was a prognostic factor. Grade I and superficial tumors (T1-T2) are the predictors of late relapses (after >24 months). The patients relapsed within the first 24 months after primary therapy had poor prognosis compared to those who relapsed in late period.
BACKGROUND: The relapses of colorectal cancer (CRC) frequently occur in 2 years period after the time of diagnosis. However, a considerable proportion of patients relapse in the late period. AIM: The aim of the present study is to define the factors predicting the early and late relapses of patients with early stage CRC. MATERIALS AND METHODS: A total of 250 patients with CRC, who relapsed after completion of primary therapy between 2005 and 2014, were enrolled in the study. According to the time of relapse, patients were divided into two groups as follows: Early relapse (Group 1: Within first 24 months) and late relapse (Group 2: Later than 24 months). Clinicopathological features and survival rates of the two groups were compared. RESULTS: Of 250 patients, 151 (60.4%) (Group 1) were relapsed within the first 24 months after completion of the primary therapy and 105 (39.6%) were relapsed later than 24 months. The patients with T1-T2 and Grade I tumors were relapsed in late period (P < 0.05). The rates of administered systemic chemotherapy and targeted therapies after relapse were similar in both groups. The median overall survival rates in patients relapsed within the first 24 months and after 24 months were 18 months and 21 months, respectively (P = 0.05). CONCLUSIONS: In patients with CRC, the time duration of relapse after completion of the operation and adjuvant chemotherapy was a prognostic factor. Grade I and superficial tumors (T1-T2) are the predictors of late relapses (after >24 months). The patients relapsed within the first 24 months after primary therapy had poor prognosis compared to those who relapsed in late period.